Throughout the Space Age, suborbital flight has been the least exciting segment of the launch market. Operating in the shadow of their much larger orbital cousins, sounding rockets carrying scientific instruments, microgravity experiments and technology demonstrations have flown to the fringes of space with little fanfare or media attention.

The suborbital sector has become much more dynamic in recent years now that billionaires have started spending money in it. Jeff Bezos’s Blue Origin and Richard Branson’s Virgin Galactic both made significant progress last year in testing New Shepard and SpaceShipTwo, respectively. Their achievements have raised the real possibility of suborbital space tourism flights in 2019. (I know. Promises, promises…. But, this year they might finally really do it. I think.)